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I am wondering what is difference between scripting and non scripting language. For example like LUA and C++. Because in game development I often read that they are hiring programmer who must know scripting language. Thank you!
Some of this is somewhat historical in nature.
Non-scripted languages like C and C++ are compiled into "raw machine code" (RMC).
That RMC is then run directly on the machine. Note that RMC is typically
very specific to the underlying CPU/hardware AND to the supporting Operating
System. So if you want to run a C program on both linux and windows, it has to be
compiled for each (two copies to maintain and distribute).
A scripted language is typically NOT compiled. Instead, the source
code is passed to an interpreter that understands the language. The
interpreter itself is typically written in a language that is
itself compiled to RMC. The interpreter's task is to read the
scripted language, and translate that into operations done by RMC.
The line has blurred in recent years (decades?) with the advent of
systems like Java. With languages like Java, source code is
compiled to an intermediate/portable language, and the Java Virtual
Machine handles the translation of that portable language into
operations for the target CPU/OS.
I am looking for the best scripting language interpreter for cross compiling to an ARM processor. Here are the requirements for "best":
Its small. Ideally, I'd like to be able to decide which parts of the language and "standard" libraries that are supported. (For instance: file system, nah don't want that. Floating point math, nope don't want that either.)
Its easy. Ideally, I'd like some documentation/tutorial/examples on how to do the cross-compile.
The goal: I'm writing a small, simple web server in an embedded ARM device and I'd like to do some string processing easily. The code is currently written in C.
I'd like the server and system-level code to be in C. I'd like to write the web "application" in a scripting language. The language features I'm most interested in are:
built-in string support
built-in regex support
built-in map support (i.e key-value pairs object)
I'd like the "best" to come from the following list: Perl, Python, Ruby, Lua. But I would be open to other language suggestions.
I would consider Lua.
Lua is distributed in a small package and builds out-of-the-box in all
platforms that have an ANSI/ISO C compiler. Lua runs on all flavors of
Unix and Windows, and also on mobile devices (such as handheld
computers and cell phones that use BREW, Symbian, Pocket PC, etc.) and
embedded microprocessors (such as ARM and Rabbit) for applications
like Lego MindStorms.
Pattern matching in Lua
Lua tables should meet your map requirement.
Lua string manipulation
Lua compared to Python
(Note: I really like Python and for general purpose scriping would prefer it to Lua but in terms of portability and performance on embedded processors I'd lean towards Lua).
I spoke about developing a programming language. Instead of making it compiled i am considering making it interpreted. So what i like to do is parse the syntax myself, build the AST and output source in an existing scripting language.
The thing i'd like to know is what interpreted language can i leverage for debugging? I'd like a call stack, file/source name and line #, to modify variables on the fly, etc.
What IDE must i use? i like visual studios but i presume it has no support for any interpreted languages
You should use Eclipse to do what you want. There is a lot of any interpreted language supports and you can easily debug with the Debug Perspective.
The advantage of the Python language is that all is open-source. Indeed, there is no obfuscation and you can watch the source code without any problem.
Assuming you can get a dynamic interpreter; can statically compiled languages replace scripting language? I never quite understood why anyone would use a scripting language? I am talking about on PC, not a limited system which needs a simplistic interpreter. I seen some python install scripts and seen similar python and C# solutions to a problem. So why use a scripting language?
NOTE: There are things that bother me about C#, i am not asking why not use C# instead. I am asking why use a scripting language? I find static compiled languages much easier to debug and often easier to code in.
There is very little distinction these days between compiling and interpreting. Look at how an interpreted language is executed - the first step is to convert the script into some kind of internal executable form, like byte code that can be executed by a simpler instruction set. This is essentially compilation to a virtual machine format. This is exactly what modern compiled languages do. And when compiled languages are deployed in server-side web apps, they even recompile from the source on the fly. So there's practically no difference in terms of the compile/execute technique.
The only difference is in the details of the instruction set, specifically in the type system. Scripting languages are usually (but not always) dynamically typed. But many large applications are also written in dynamically typed languages too. So again, there is no clear distinction here.
Personally I think static typing, far from being "extra unnecessary effort" (as it is often described) is actually a huge productivity booster, making it much easier to write short snippets correctly on the first attempt, thanks to intellisense/autocompletion. To underline this, look at how Microsoft has improved the jQuery library simply by adding static type information to it (in specially formatted comments) so we can have intellisense in the IDE.
And meanwhile, static languages (including C# and Java) are bringing in more dynamic typing features.
So I see these categories as eventually merging and the distinction being meaningless.
Wikipedia says that a Scripting Language is a language that controls other software. You can do that with C#, but true scripting languages like Powershell are designed specifically for this.
I tend to think of a scripting language in more "interactive" terms than C#. With a scripting language, you can write a line or two of code, execute it and see the results immediately. That's not so easy in C#, where you have to put your code in a Console Application, or fire it off from a unit test, or type it into the Immediate window where you don't have intellisense.
That rapid cycle of write, execute allows rapid prototyping of complete "scripts" in a scripting language, because it gives you immediate feedback on each line of code.
This kind of question often starts flame wars as people are passionate about their respective camps.
In the computer olden days, Unix command line tools and console shells provided a rich scripting environment where all sorts of processing could be done. You didn't need to be an expert programmer in any specific language and could string (pun intended) various programs (other people wrote) together using the pipe structure to massage your data which was mostly text not binary related. It is quick and easy to make changes to your batch command file. You don't have a source file that has to be edited, compiled linked with external static or shared libries/DLLS in the case of Windows.
One thing scripting does not have normally have is speed. You don't write device drives and live internet trading AI systems in scripting. But if you run a script once a day on some data received via e-mail or ftp you don't normally care how long it takes as it can run it background anyway.
Rewind back to the present and the waters become muddy. Some scripting enviroments offer a kind of speed up facility where they will read you script and almost compile and link in modules the same a normal C++ or VB program might use for speed puposes. But this very iffy and can't be relied on.
So how do you choose which route to go. Start doing tasks using scripting. If it runs too slow or you are having to do stuff every 5 minutes then parts of your script might benifit from a section written in a traditional language or the whole thing could be written in a language.
Like anything dabble and learn
Each is used for different purposes. Programs written in scripting languages are often not self-contained; they often function as "glue code" or (as Robert Harvey mentions) to automate a task. You often find scripting language interpreters embedded within an application (cf Python in Blender; Guile, Perl and Python in GIMP; JS in umpteen different browsers; Lua in countless games). Compiled languages, on the other hand, are used to produce self-contained applications. Scripts are mostly cross-platform; compiled applications usually aren't.
Note that a scripting language doesn't necessarily use an interactive interpreter (e.g. Perl), and an interpreted language isn't necessarily use for scripts (e.g. games made using PyGame). Note also that there's nothing about the languages themselves that make them interpreted or compiled. You could have a C# interpreter or a Ruby compiler. There have been a number of Lisp systems that offered both interpreters and compilers.
I would call my shell (bash) a scripting language, and I don't see a replacement comming, which is compiled.
I like to use scala, which is a statically typed language which comes with an interpreter-like REPL-interface, and due to type interference looks pretty much like a scripting language; have a look here: http://www.simplyscala.com/ .
But it isn't meant to be the glue between other programs as the shell is, so for small jobs, which are easily verified by hand and eye, which are just a few lines of code, I prefer to use the shell. And jumping from directory to directory is comfortable in a shell, where the prompt shows where I am.
Before we begin, I don't think that I've ever met a static language user who "got" scripting language without trying them, including myself. It is a different experience.
So no. Basically, you can add features to static languages which makes them superficially seem like scripting languages (like simple type inference), but its not the same:
Many scripting language users hate static languages. They feel constrained. Scripting languages are typically very good at not getting in the users way, which is sacrificed in static languages for speed/correctness.
Duck typing will not appear in static languages.
Scripting language users don't like type annotations. Its not really possible to provide a type-inference system for scripting languages, and the simple type inference appearing in some languages now only works for static types.
Techniques like monkey patching (which to my mind is a very bad idea) is pervasive in Ruby, and allows for very powerful techniques, which won't become available soon in static languages either.
Which isn't to say that a yet-to-be-designed language can't handle scripting language features in a relatively static way, but it would be difficult for it to become popular relative to the entrenched Python/PHP/Perl/Ruby/Javascript set. Factor is the closest thing, AFAICT.
What will happen is that scripting language implementations will get faster by using JITs.
Can a screw driver replace a hammer ? No, because you just don't use them for the same purpose. And if both exist, and if such a lot of people use either one or the other, there must be a reason...
Same anwser for :
class inheritance vs prototype;
imperative vs oo;
static vs dynamic typing;
strongly vs weakly typed;
manual memory management vs GC;
C# vs Java;
blue vs red;
man vs woman;
batman vs superman (but I do think superman would win... wait, there is kryptonite... oh man, I don't know...)
etc...
Because it is shorter to write since it is a higher level language, and it doesn't need the compilation cycle which also makes thing shorter.
I am asking why use a scripting
language? I find static compiled
languages much easier to debug and
often easier to code in.
Because I find loosely-typed dynamic languages without an explicit compile-run cycle much easier to debug and generally easier to code in.
As already discussed in "Lua as a general-purpose scripting language?" Lua currently probably isn't the best scripting language for the desktop environment.
But what do you think about the future? Will Lua get so popular that there will soon be enough libraries to be able to use it like Python, Ruby or something similar?
Or will it simply stay in it's WoW niche and that's it?
I think it has a great future, a lot of projects are starting to adopt it for it's simplicity and usefulness.
Example: Awesome WM (Window Manager)
The project recently released version 3, incorporating a new configuration system completely written in Lua. Allowing you to literally write your configuration file as a program, loops, booleans, data structures.
Personally I love the syntax and the flexibility of such a system, I think it has great potential.
I wouldn't be surprised if it became more popular in the future.
Brian G
I suppose the answer starts with 'It depends how you want to use it...'.
If you're writing the common business app (fetch the data from the database, display the data in a web page or window, save the data to the database), Lua already has what you need.
The Kepler Project contains goodies for web development. Check out their modules to see some of the available libraries - there's network, MVC, DBMS access, XML, zip, WSAPI, docs...
As an example web app, check out Sputnik.
For desktop UI, there's wxLua - Lua hooks for wxWidgets.
ORM is conspicuously missing but that didn't stop people from developing in other languages before ORM was available.
If you're looking for specialized libraries - scientific, multimedia , security - don't count Lua out before you check LuaForge.
When it comes down to it, there's nothing in Lua's design that prevents general purpose use. It just happens to be small, fast, and easy to embed... so people do.
Uh? I would say instead WoW is a niche in the Lua ecosystem... The world of Lua doesn't revolve around WoW, there are lot of applications, some big like Adobe Lightroom (to take a non game), using Lua.
Lua is initially a scripting language, in the initial sense, ie. made to be embedded in an application to script it. But it is also designed as an extensible language, so we will see progressively more and more bindings of various libraries for various purposes.
But you will never get an official big distribution with batteries included, like Python or Perl, because it is just not the philosophy of the authors.
Which doesn't prevent other people to make distributions including lot of features out of the box (for Windows, particularly, where it is difficult to build the softwares).
Lot of people already use it for general system-level scripting, desktop applications, and such anyway.
There are more and more libraries for Lua.
If you are a Windows user, have look at Lua for Windows. It comes with "batteries included" (wxLua, LuaCURL, LuaUnit, getopt, LuaXML, LPeg...).
Very usefull!
It's 2017, 9 years after this question was first asked, and lua is now being heavily used in the field of machine learning due to the Torch library.
I really like it as an embedded language. It's small, very easy to use and embed and mostly does what I need right out of the box. It's also similar enough to most languages that it has never really been an issue for me. I also like how easy it is to redefine and add base functions and keywords to the language to suit whatever needs my application has.
I have used it in the WoW area but I've also found it useful as a generic scripting language for a number of different applications I've worked on, including as a type of database trigger. I like Ruby and Python and other more full-featured scripting languages but they're not nearly as convenient for embedding in small applications to give users more options for customizing their environments.
being comfortable as a shell language has nothing to do with being a great general purpose language.
i, for one, don't use it embedded in other applications; i write my applications in Lua, and anything 'extra' is a special-purpose library, either in Lua or in C.
Also, being 'popular' isn't so important. in the Lua-users list periodically someone appears that says "Lua won't be popular unless it does X!", and the usual answer is either: "great!, write it!", or "already discussed and rejected".
I think the great feature of Lua is, that it is very easily extensible. It is very easy to add the Lua interpreter to a program of your own (e.g. one written in C, C++ or Obj-C) and with just a few lines of code, you can give Lua access to any system resource you can think of. E.g. Lua offers no function to do xxx. Write one and make it available to Lua. But it's also possible the other way round. Write your own Lua extension in a language of your choice (one that is compilable), compile it into a native library, load the library within Lua and you can use the function.
That said, Lua might not be the best choice as a standalone crossplatform language. But Lua is a great language to add scripting support to your application in a crossplatform manner (if your app is crossplatform, the better!). I think Lua will have a future and I think you can expect that this language will constantly gain popularity in the long run.
Warhammer Online, and World of Warcraft use it for their addon language I believe.
I think it's hot! I'm just no good at it!
Well, greetings from 2022.
It is already a general purpose language. Today you can even serve pages using OpenResty, extend games, read databases or create scripts as shellscript replacements.
There are a plenty of libraries "modules" for Lua, many ways to achieve what you are wanting and Lua 5.4 is even faster.
The "extendable and extensive" nature of Lua, accostumed people to think it should only be used as plugin or extension. In Linux, by example, you can shebang a file with lua-any, make it executable and run like any system script. Or you can make a folder app like Python or virtualenv using Lupe. Lua 5.3 also gained impressive performance improvements.
Also there are many good tools like IUP to create native windows in Lua for Mac, BSD, Linux and Windows and side environments like Terra that lets you use Lua with its counterpart Terra and write compiled programs. Lua now, is more than a extension language, it has its own universe.